Rx free buffer register, So the – Digi NS9750 User Manual
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E t h e r n e t C o m m u n i c a t i o n M o d u l e
RX Free Buffer register
Address: A060 0A3C
So the
RX_RD
logic knows when the software is freeing a buffer for reuse, the
software writes to the RXFREE register each time it frees a buffer in one of the pools.
RXFREE has an individual bit for each pool; this bit is set to 1 when the register is
written. Reads to RXFREE always return all 0s.
Register bit assignment
Bits
Access
Mnemonic
Reset
Description
D31:04
N/A
Reserved
N/A
N/A
D03
W
RXFREED
0
Pool D free bit
D02
W
RXFREEC
0
Pool C free bit
D01
W
RXFREEB
0
Pool B free bit
D00
W
RXFREEA
0
Pool A free bit
Table 250: RX Free Buffer register
Reserved
RX
FREED
RX
FREEA
13
12
11
10
9
8
7
6
5
4
3
2
1
0
15
14
31
29
28
27
26
25
24
23
22
21
20
19
18
17
16
30
Reserved
RX
FREEC
RX
FREEB